diff --git a/beacon_node/beacon_chain/test_harness/tests/chain.rs b/beacon_node/beacon_chain/test_harness/tests/chain.rs
index e72c3a5aa..d47de6889 100644
--- a/beacon_node/beacon_chain/test_harness/tests/chain.rs
+++ b/beacon_node/beacon_chain/test_harness/tests/chain.rs
@@ -1,3 +1,5 @@
+#![cfg(not(debug_assertions))]
+
 use env_logger::{Builder, Env};
 use log::debug;
 use test_harness::BeaconChainHarness;
diff --git a/eth2/fork_choice/tests/tests.rs b/eth2/fork_choice/tests/tests.rs
index 3ce63eeb7..fb530ac43 100644
--- a/eth2/fork_choice/tests/tests.rs
+++ b/eth2/fork_choice/tests/tests.rs
@@ -1,3 +1,4 @@
+#![cfg(not(debug_assertions))]
 // Tests the available fork-choice algorithms
 
 extern crate beacon_chain;
diff --git a/eth2/state_processing/tests/tests.rs b/eth2/state_processing/tests/tests.rs
index fcd034158..e80340e9a 100644
--- a/eth2/state_processing/tests/tests.rs
+++ b/eth2/state_processing/tests/tests.rs
@@ -1,6 +1,7 @@
+#![cfg(not(debug_assertions))]
+
 use serde_derive::Deserialize;
 use serde_yaml;
-#[cfg(not(debug_assertions))]
 use state_processing::{per_block_processing, per_slot_processing};
 use std::{fs::File, io::prelude::*, path::PathBuf};
 use types::*;
diff --git a/eth2/types/src/beacon_block_header.rs b/eth2/types/src/beacon_block_header.rs
index fa71bd26b..e4db3a721 100644
--- a/eth2/types/src/beacon_block_header.rs
+++ b/eth2/types/src/beacon_block_header.rs
@@ -5,7 +5,7 @@ use rand::RngCore;
 use serde_derive::{Deserialize, Serialize};
 use ssz_derive::{Decode, Encode};
 use test_random_derive::TestRandom;
-use tree_hash::TreeHash;
+use tree_hash::{SignedRoot, TreeHash};
 use tree_hash_derive::{SignedRoot, TreeHash};
 
 /// A header of a `BeaconBlock`.
@@ -37,7 +37,7 @@ impl BeaconBlockHeader {
     ///
     /// Spec v0.5.1
     pub fn canonical_root(&self) -> Hash256 {
-        Hash256::from_slice(&self.tree_hash_root()[..])
+        Hash256::from_slice(&self.signed_root()[..])
     }
 
     /// Given a `body`, consumes `self` and returns a complete `BeaconBlock`.
diff --git a/eth2/utils/boolean-bitfield/src/lib.rs b/eth2/utils/boolean-bitfield/src/lib.rs
index a744c9498..1d0f1c02e 100644
--- a/eth2/utils/boolean-bitfield/src/lib.rs
+++ b/eth2/utils/boolean-bitfield/src/lib.rs
@@ -9,7 +9,6 @@ use serde_hex::{encode, PrefixedHexVisitor};
 use ssz::{Decodable, Encodable};
 use std::cmp;
 use std::default;
-use tree_hash::tree_hash_ssz_encoding_as_list;
 
 /// A BooleanBitfield represents a set of booleans compactly stored as a vector of bits.
 /// The BooleanBitfield is given a fixed size during construction. Reads outside of the current size return an out-of-bounds error. Writes outside of the current size expand the size of the set.
diff --git a/eth2/utils/ssz_derive/src/lib.rs b/eth2/utils/ssz_derive/src/lib.rs
index f3475f5a7..c5b53e934 100644
--- a/eth2/utils/ssz_derive/src/lib.rs
+++ b/eth2/utils/ssz_derive/src/lib.rs
@@ -38,7 +38,7 @@
 extern crate proc_macro;
 
 use proc_macro::TokenStream;
-use quote::{quote, ToTokens};
+use quote::quote;
 use syn::{parse_macro_input, DeriveInput};
 
 /// Returns a Vec of `syn::Ident` for each named field in the struct.